Revert 241144 "Implement chromium's TLS."

trunk/src/base/threading/thread_local_storage.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef BASE_THREADING_THREAD_LOCAL_STORAGE_H_
 #define BASE_THREADING_THREAD_LOCAL_STORAGE_H_
 
 #include "base/base_export.h"
 #include "base/basictypes.h"
 
-#if defined(OS_WIN)
-#include <windows.h>
-#elif defined(OS_POSIX)
+#if defined(OS_POSIX)
 #include <pthread.h>
 #endif
 
 namespace base {
 
-namespace internal {
-
-// WARNING: You should *NOT* be using this class directly.
-// PlatformThreadLocalStorage is low-level abstraction to the OS's TLS
-// interface, you should instead be using ThreadLocalStorage::StaticSlot/Slot.
-class BASE_EXPORT PlatformThreadLocalStorage {
- public:
-
-#if defined(OS_WIN)
-  typedef unsigned long TLSKey;
-  enum { TLS_KEY_OUT_OF_INDEXES = TLS_OUT_OF_INDEXES };
-#elif defined(OS_POSIX)
-  typedef pthread_key_t TLSKey;
-  // The following is a "reserved key" which is used in our generic Chromium
-  // ThreadLocalStorage implementation.  We expect that an OS will not return
-  // such a key, but if it is returned (i.e., the OS tries to allocate it) we
-  // will just request another key.
-  enum { TLS_KEY_OUT_OF_INDEXES = 0x7FFFFFFF };
-#endif
-
-  // The following methods need to be supported on each OS platform, so that
-  // the Chromium ThreadLocalStore functionality can be constructed.
-  // Chromium will use these methods to acquire a single OS slot, and then use
-  // that to support a much larger number of Chromium slots (independent of the
-  // OS restrictions).
-  // The following returns true if it successfully is able to return an OS
-  // key in |key|.
-  static bool AllocTLS(TLSKey* key);
-  // Note: FreeTLS() doesn't have to be called, it is fine with this leak, OS
-  // might not reuse released slot, you might just reset the TLS value with
-  // SetTLSValue().
-  static void FreeTLS(TLSKey key);
-  static void SetTLSValue(TLSKey key, void* value);
-  static void* GetTLSValue(TLSKey key);
-
-  // Each platform (OS implementation) is required to call this method on each
-  // terminating thread when the thread is about to terminate.  This method
-  // will then call all registered destructors for slots in Chromium
-  // ThreadLocalStorage, until there are no slot values remaining as having
-  // been set on this thread.
-  // Destructors may end up being called multiple times on a terminating
-  // thread, as other destructors may re-set slots that were previously
-  // destroyed.
-#if defined(OS_WIN)
-  // Since Windows which doesn't support TLS destructor, the implementation
-  // should use GetTLSValue() to retrieve the value of TLS slot.
-  static void OnThreadExit();
-#elif defined(OS_POSIX)
-  // |Value| is the data stored in TLS slot, The implementation can't use
-  // GetTLSValue() to retrieve the value of slot as it has already been reset
-  // in Posix.
-  static void OnThreadExit(void* value);
-#endif
-};
-
-}  // namespace internal
-
 // Wrapper for thread local storage.  This class doesn't do much except provide
 // an API for portability.
 class BASE_EXPORT ThreadLocalStorage {
  public:
 
   // Prototype for the TLS destructor function, which can be optionally used to
   // cleanup thread local storage on thread exit.  'value' is the data that is
   // stored in thread local storage.
   typedef void (*TLSDestructorFunc)(void* value);
 
@@ skipping 26 matching lines @@
     void* Get() const;
 
     // Set the thread-local value stored in slot 'slot' to
     // value 'value'.
     void Set(void* value);
 
     bool initialized() const { return initialized_; }
 
     // The internals of this struct should be considered private.
     bool initialized_;
+#if defined(OS_WIN)
     int slot_;
+#elif defined(OS_POSIX)
+    pthread_key_t key_;
+#endif
+
   };
 
   // A convenience wrapper around StaticSlot with a constructor. Can be used
   // as a member variable.
   class BASE_EXPORT Slot : public StaticSlot {
    public:
     // Calls StaticSlot::Initialize().
     explicit Slot(TLSDestructorFunc destructor = NULL);
 
    private:
     using StaticSlot::initialized_;
+#if defined(OS_WIN)
     using StaticSlot::slot_;
-
+#elif defined(OS_POSIX)
+    using StaticSlot::key_;
+#endif
     DISALLOW_COPY_AND_ASSIGN(Slot);
   };
 
   DISALLOW_COPY_AND_ASSIGN(ThreadLocalStorage);
 };
 
 }  // namespace base
 
 #endif  // BASE_THREADING_THREAD_LOCAL_STORAGE_H_